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Rett Syndrome

(Rett’s Disorder)

Definition

Rett syndrome is a problem with the development of the nervous system. It is most common in girls. Boys with Rett syndrome are usually stillborn or die shortly after birth.

Many people with Rett syndrome live into adulthood. Most have severe disabilities, including an inability to talk or walk.

Causes

Rett syndrome is most often caused by nonhereditary mutations on a specific gene on one X chromosome.

Females have two X chromosomes. Males have one X and one Y chromosome. Males usually die from Rett syndrome because they lack a second normal X chromosome. The second normal X chromosome in girls may provide some protection.

In Rett syndrome, the mutated gene affects methyl cytosine binding protein 2 (MECP2). When it is mutated, there is a deficiency of this important protein. Not everyone with the MECP2 mutation will have Rett syndrome. Some females may be normal or have only mild symptoms.

It is not clear what causes the Rett gene to mutate. Rett syndrome is usually nonhereditary. This means it does not run in families.

Risk Factors

There are no known risk factors for Rett syndrome.

Symptoms

Children with Rett syndrome will start developing normally. They will smile, move, and pick items up with their fingers. But by 18 months of age, the developmental process seems to stop or reverse itself. The age of onset and the severity of symptoms is different from person to person. There are 4 stages. Symptoms for each stage include:

Diagnosis

You will be asked about your child’s symptoms and medical history. A physical and neurological exam will be done. Genetic testing can often confirm the diagnosis. Your doctor may also do tests to rule out other conditions, like
autism.

Some symptoms of Rett syndrome are similar to those of autism. Children with autism, who are more often boys, do not maintain person-to-person contact. Most girls with Rett syndrome, though, prefer human contact to focusing on inanimate objects. These differences may give the first clue in diagnosing Rett syndrome.

Physical and developmental symptoms can often lead your doctor to a Rett syndrome diagnosis.

Your child's bodily fluids may be tested. This can be done with blood tests.

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.